Artificial limb



C. D. BLATCHFORD ARTIFICIAL LIMB.

APPLICATION FILED JAN-21,1918.

Pat nted Mar. 23, 1920.

c. n. BLATCHFORD.

ARTIFICIAL LIMB.

APPLlCATlOh FILED JAN-21,1918.

m a Z, a %m ,w Z fly 0M Z mm a A wfl w M 2 a 0.

CHARLES DUNCAN BLA'ICHEEORD, OF LONDON, ENGLAND.

ARTIFICIAL LIMB.

Specificationof Letters Patent. Patented B131. 23, 1920.

Application filed January 21, 1913; Serial no. 213,046.

To all whom it may concern:

Be it known that I, CHARLES DUNCAN BLATCIIFORD, a subject of His Majesty the King of England, and resident of London, Kingdom of England, have invented certain new and useful Improvements in or Relating to Artificial Limbs, of which the following is a specification.

This invention relates to improvements in the construction of the joints and locking means of artificial limbs.

Heretofore it has been proposed to cause the forearm of an artificial arm to turn about the elbow pivot by tightening or drawing up a cord or strap which is attached at one end to the shoulder or body of the wearer and at its other end to the said forearm, the said cord being guided over suitable pulleys or curved surfaces provided at the joint.

Now according to the chief features of the present invention the lower end of the cord or strap is attached to a sector, drum or disk which is secured to the forearm or lower limbmember or to the elbow or other pivot pin carried thereby, so that whenthe strap is pulled the sector, drum, or disk and the forearm will move together. Further I preferably provide spring controlled looking means at the joint whereby the parts may be positively locked against movement in both directions.

The invention is especially applicable for artificial arms for use where amputation has been effected above, through, below the elbow, or through the wrist, or legs where amputation has been effected above, below, or through the knee or through the ankle, for excision at thehip,or for shoulder amputation.

The invention is illustrated in and hereinafter described with reference to the accompanying drawings in which-:

Figure 1 isa side elevation of an adjustable artificial arm intended for use where amputation of the original limb has been effected at the upper or middle third of the forearm; N

Fig. 2is a similar View showing the forearm raised;

Fig. 3* is a front elevation of said arm corresponding in position Fig. 1

Fig. at a sectional side elevation. of an adjustable artificial arm intended for use where amputation of the original limb has been effected at the shoulder or at the lower, middle or upper third of the upper arm;

F ig. 5 is a sectional front elevation of said arm; and

Fig. 6 is a reverse side elevation.

As shown in Figs. 1, 2 and 3, and atthe pivot 01" joint of the forearm and upper arm (a, b respectively, a sector 0 is provided an integral part of the portion a it is desired to move. The sector 0 may be replaced by a drum or a disk. To this sector 0 one end of a chain (5, stranded wire cable, or the like (5 is suitably secured on the front or inside of the joint which, in the construction shown, is formed by a pair of pivot pins or studs 6 which unite the pairs of side straps to, Z) of the parts a, Z) respectively. This wire or the like cl is connected to a cord or strap cl and passes away from the sector 0, drum or disk around the back of suitable guide pulleys f, g and up to the back or other convenient part of the shoulder or the body to which it is secured in the known way by straps or in any other preferred manner. movement of the upper arm or the stump thereof, where only a small portion remains, will cause the chain (Z and strap (Z to be pulled and will, by reason of the before described joint connection or sector 0, cause the forearm o to be simultaneously moved up or forward, and vice versa when the upper arm or stump is lowered or moved back.

In the case of an artificial leg the joint Thus the upward or forward would be arranged so as to produce the forward movement of the lower leg, but for shoulder amputations the strap would be connected across the wearers back to the opposite shoulder so thatthe movement of one shoulder would serve to control the arm. The sector 0, drum or disk may be arranged centrally within the jointwhere possible, as shown in Figs. 4, 5 and 6, instead of at the side according to the previously described construction of the limb. In this latter arrangement the sector 0 is secured to a transverse pivot pin 0 which passes through the lower solid portion of the up 60 r limb member, pivoted to an upper limb memper arm I) to engage the lower pair of side straps a as shown. I

I may also provide at the joint or pivot of the elbow a clutchor locking means which can either be adapted to normally maintain a rigid joint or to be normally free. Preferably the pivot pin 6 at th joint is as shown provided with a notched quadrant h adapted to be engaged by a spring-pressed pawl i when it is required to maintain a rigid joint. For the purpose of withdrawing the pawl i suitable transmission mechanism, such as a strap 1', wire or other fiexible member, is attached thereto and, after passing up the arm under a suitable guide member 7a is connectedto suitable adjustable strapping on the body of the wearer.

Thus, if the parts are properly adjusted expans'ion of the chestor movement of the wearers shoulder will cause the sprmg- V pressed pawl 71 to be withdrawn from enabout a pivot Z, Fig. '5, on a block mwhich inits turn is mounted to turn about another pivot n at right angles to the first pivot. By this means the pawl 13 can be raised and moved laterally when desired into a side slot 0 formed in the fixing plate 79 parallel with the main guide slot in which the said pawl normally moves, thus permitting the locking mechanism to be used or put 'out of action at will. Preferably the improved stop or locking means are used in conjunction with'the limb actuating means of the kind previously described, in which case the limb can be adjusted and. locked in any set position with the utmost facility while leaving the otherdimbsof the wearer quite free.

It should be understood that no broad claim is made to the use of spring retained locking means except in connection with the improved joint meehanism of the kind above described, and which locking means is designed to positively lock the parts against movement in both directions.

What I claim is: r w

1. An artificial limb comprising a lower ber, a' sect or connectedto the lower limb member, an appendage having one of its ends connected to said sector and its other end to-the body of 'thewearer; and by means of which the relative movements of the limb members are mechanically controlled, a notched quadrant adapted to move with the lower limb member, and a spring pressed locking device which coiiperates with said notched quadrant to prevent movement of said lower limb member in both directions.

2. An artificial limb comprising a lower limb member pivoted to an upper limb member, a sector connected to the lower limb member, an appendage having one of its ends connected to said sector and its other end to the body of the wearer, a notched quadrant adapted to move with the lower limb member, a spring pressed pawl which cooperates with said notched quadrant, and means whereby said pawl can be rendered inoperative. 1

3. An artificial limb comprising a. lower limb memberpivoted to an upper limb member, a sector connected to the lower limb member, an appendage having one of its ends connected to said sector and its other end to the body of the wearer, a notched quadrant adapted to move with the lower limb member, a doubly pivoted springpressed pawl which cooperates with said notched quadrant, and a plate formed with a side slot into which said pawl can be moved laterally to render it inoperative.

4. An artificial limb jointed to bend in one direction only and comprising a lower limb member pivotally connected to an upper limb member, a single winding drum sector carried by the lower limb member and disposed in the bend of the limb so as to be concentric to the pivot of the joint, a guide pulley carried by the upper limb member, and an appendage connected to the winding drum sector at its one end and at its other end adapted to be connected to the body of the wearer, the whole arrangement and connection of the aforesaid parts being essentially such that the appendage is wound on the said drum when the limb is extended and unwound when the limb is bent thus enabling the said limb to be positively raised or moved against gravity when the said appendage is pulled.

5. An artificial limb jointed to bend in one direction only and comprising a lower limb member pivotally connected to an upper limb member, a single winding drum sector carried by the lower limb member and dis posed in the bend of the limb so as to be concentric to the pivot of the joint, 3. guide pulley, carried by the upper limb member, an appendage connected to the windin drum sector at its one end and at its other end adapted to be connected to the body of the wearer, the whole arrangement and connection of the aforesaid parts being essentially such that the appendage is wound on the said drum when the limb is extended and unwoundwhen the limb is bent thus enabling the said limb to be positively raised or moved against gravity when the said appendage is pulled, a notched quadrant adapted to move with the lower limb member, a spring pressed pawl or arm 00- operating with the said notched quadrant to adjustably lock the limb against movement in both directions and means whereby the said pawl can be rendered inoperative at will.

In testimony whereof I have hereunto signed my name.

CHARLES DUNGAN BLATCHFORD. 

